Waste disposal containers come in a variety of shapes and sizes, are made of a variety of materials, and may be adapted for a variety of purposes, including indoor and outdoor use. Common indoor residential waste containers are generally made of plastic materials and have a capacity in the range of one to thirty gallons. Outdoor waste disposal containers tend to be larger, with common residential waste disposal containers ranging in capacity from fifty to one hundred gallons. Many waste disposal containers include a bin that collects and holds waste, and a lid. The lid can be removed or opened when adding waste to the bin, but otherwise remains closed, so as to contain odors emanating from the waste as well as to keep the waste out of sight. With outdoor waste disposal containers in particular, the container lid also prevents the contents of the bin from being blown out of the container by wind, and prevents small animals such as dogs, cats, raccoons, and birds from accessing and/or removing the contents of the container.
U.S. Pat. No. 7,100,791, the entirety of which is incorporated by reference herein, describes a hinged lid trash can for curbside refuse pickup. The can is equipped with wheels to facilitate movement of the can from a residence to a curbside location for pickup. The wheels are positioned adjacent the rear bottom corners of the can, at a sufficient height to barely contact the ground (or to not contact the ground) when the can is in a resting position. When the can is rotated backward, the wheels contact the ground and bear the weight of the can, such that the can may be more easily moved from one location to another. The can also includes a reinforced flange and a latch bar on the front wall of the can. A refuse truck with a mechanical arm can then use the mechanical arm to engage the flange and latch bar of the can and lift the can into the air. The mechanical arm inverts the can over the truck's refuse bin, where the force of gravity causes the lid to swing open and the contents of the can to fall into the refuse bin. As the can is lowered to the ground by the mechanical arm, the lid swings back into a closed position.
In certain areas, waste disposal containers are needed that not only prevent access to the contents thereof by small animals, but also by bears and other large animals. Bears are known to have a keen sense of smell, and are often attracted to the smell of food from waste disposal containers. However, access to full garbage cans by bears can be dangerous to both bears and humans. Accordingly, various waste disposal containers have been designed to prevent bears from gaining access to the content thereof. For example, U.S. Pat. No. 7,748,558 describes a latch for a refuse container that utilizes a complicated system of plates, springs, cables, and rods to prevent access to the refuse container by a bear.